As a flush toilet device which temporarily receives waste and discharges the waste with flush water, a flush toilet device described in the following Patent Document 1 has been proposed. As shown in FIG. 1 in the following patent document, the flush toilet device described in the following Patent Document 1 includes a bowl which has a waste receiving surface for temporarily receiving waste, flush water supply means, such as a water reservoir tank, for supplying flush water to the bowl, an inlet portion which is connected to a lower side of the bowl, a rising conduit which is formed so as to extend upward from the inlet port, a lowering conduit which is formed so as to extend downward from the end of the rising conduit, and a discharge water trap conduit which reserves water from the inlet portion to at least a part of the rising conduit as retained water when the flush toilet device is not in use and forms sealing water with at least a part of the retained water.